Steering by driving interlocked with manual steering



p 1953 R. LAPSLEY ET AL STEERING BY DRIVING INTERLOCKED WITH MANUAL STEERING s She ets-Sheet 1 Filed Nov. 14, 1949 INVENTOR. LAPSLEY ROBERT GEORGE L. TURNER ATTY.

p 8,1953 R. LAPSLEY ET AL 2,651,377

STEERING BY DRIVING INTERLOCKED WITH MANUAL STEERING Filed Nov. 14, 1949 5 Sheet s-Sheet 2 FIG. 2

INVENTOR. ROBERT LAPSLEY BY GEORGE L. TURNER ATTY.

STEERING R. LAPSLEY ET AL Sept. 8, 1953 STEERING BY DRIVING INTERLOCKED WITH MANUAL 5 Sheets-Sheet 5 Filed Nov. 14, 1949 INVENTOR. LAPSLEY L. TURNER ROBERT GEORGE Patented Sept.

curred-stares PATENT om STEERING 'BY on Robert Lapsley, Berrien Turner, Niles, Mich., a ment Company, Buch tion of Michigan IVING INTERLOCKED wrrH MANUAL STEERING This invention relates'to industrial tractors and, more particularly, is concerned-withan in the type which isadaptedforward or reverse direction,- or to push in either direction for moving large dustrial tractor of to-tow, either in a trailers or similar ports and the like and similar types 7 vehicles, or used around airfor towing or pushing planes of heavy equipment.

' One of the primary objects of the present invention is to provide an industrial vehicle of this type which has'marked improvements in maneuverability eneral nature. present invention 'overprevious vehicles of this t is also the object of the to provide a vehicle of this type having a very short turning radius, so that it can be pivoted length to secure the like, while yet such size asto its use upon substantially within its own operation in limited areas and allowing the vehicle to be of have sufllcient flotation to allow floors or surfaces which do not have to be especially reinforced.

-A'still further object of the present invention is to provide a the usual type of vehicle of this type in which friction clutch normally associated with-automotive vehicles is eliminated, and'a smooth cushion-type clutching means is provided between the driving train, so that corresponding smo mechanism to be towed Oneof the featuresof providing a vehicle of this type with axle in which the Wheels at opposite resides in a 1 driving source of power and the the vehicle canexert a pulling effort upon the 'or pushed.

the present invention oth endsof the axle are independently driven and with which is asso ciated a steering wheel control so that the wheels at one side of the vehicle may be either stopped or rotated in a reverse. direction with respect to the opposite wheels,'to. produce the short turning radius, thus allowing the truck to pivot substantially about the longitudinal center of the drive axle. This is provided in con mounting of the r junction with. a caster type ear or steering wheels, with the; steering control being so arranged as to effect this driving of through turning of.

the wheels independently th'e'steering wheel, thus eliminating anyrspecial control on the part of the operator.

The invention further contemplates a mechanism where the braking efiort can be applied toi-either of the drive wheels independently, or

both. of the whereby the v'ehicl the braking action.

drive wheels simultaneously,

e can be partially steered by Springs, and George L. ssignors to Clark Equipanan, Mich., a corpora- 2 Other objects andadvantages of the present] invention will appear more fully from thejfolpresent invention.

In the drawings, Figurel'is a perspectiveviewof an industrial tractorembodying the pres ent invention. f

Figure 2 is a schematic 'lay'outof thehydraulic circuit Of our present invention embodied in the industrial tract-or of Figure 1; and Q Figure 3 is a top plan view of the industrial tractor shown in Figurel with-a diagrammatic showing of the drive means therefor J which forms the subject matter of our'present'inven tion. I r r 9 Referring now in detail to the drawings, the industrial tractor is indicated generally at '5 in Figure 1, and includes a cab 6 having'therein seats 1. Positioned in line with one or the seats 7 is the steering column 8 upon" which is mount ed the steering wheel 9 and the control member I 0. Intermediate the seats I there is an instrument panel 12, carryingsuitable instru- Also intermediate the seats are certain control levers, indicated generally at 13, for a purposeto be hereinafter described. Extending clear across the transverse p'ortion of the vehicle between the fenders H- is a wind-' shield I5, which windshield, it will'be-noted, extends down to the top of the chassis thereby giving the operator substantially clear vision'oven the forward end of the vehicle. This end ofthe vehicle is adapted to carry a pusher plate or bumper plate 16, which is provided with two-vertical slides I! within which is adapted to be or the like when used for airport work. In the rear end of the vehicle, thereisprovided a winch 20 which, preferably,'is power con trolled through one of the controllevers Hi from a power'take-ofi on the'motive power of the vehicle.

The prime mover for the vehicle is preferablyhoused within the-housing 22- extending rearwardly of the rear'wall of thecab-G and the-gas tank is preferably located in the side portion 23 of the chassis, with the closure cap being indicated at 24.

Mounted centrally of the vehicle, substantially adjacent the rear end thereof, are a pair of dual wheels 25 which, preferably, are mounted;- upon a caster support 26", as. shown:' m Figure 3, for rotation with a shaft 2! controlled by suitable linkage, indicated at 28, connected to the bell crank lever 29 which is fixed intermediate its ends upon the pivot 30, and at itsoppcsite end is connected to the drag link 32 eXtendingfOr wardly to the bottom end of the steering column 8. The drag link 32 has suitable: connection: with the steering column il-thrloughi a,ball and: socket joint Hi4 whereby rotary movement of the column 8 will produce rectilinear movement of the drag link 32.

This steering mechanism is substantially similar to that shown in the co-pending application of George La Turner, Serial No. 99,779, filed June 1. 4

Referring to Figures 2' and 3, there is: shown an arrangement for controlling the. driving torque toc. the vehicle which consists, primarily; in a. fluid drive. In this form ofthe invention, the prime mover or engine is preferably of the, internalcombustion type having the radiator 51 and having: aclutchhousing 53- to which is connected a combination hydraulic pumpand motor unit, 54 which may be. of the compound type having, three stages of delivery: of fluid: un-' der pressure which may becontrolled through any suitable; valve mechanism in conjunction with thethrottle control of the engine 50.

fIhe pump and motor unit: 54 is adaptedto have. outlet-v lines 55 and 56: leading. therefrom to fluid operated motors 51 and 58, respectively; these fluid, motors being so arranged that fluid under DIESSUI'B: will operate to impart rotarymovementto the pinion; shafts 5% extending therefrom and into-the drivehousingsfill'mounted; on: the. frame of-v thevehicleand supporting the wheel spindles-:62. Mountedon the-wheel spindies 62- are the drive wheels fia: and. e4- at, opposite; sides: ofthe: vehicle, thepinion 5% driving suit-s ablaring; gears 65 connected to" the spindles (12 forv imparting rotary movement to the driving wheelsv 'Iihespecial' fluid control system for the vehicle shown inFigure'3 isshowndiagrammati-- cally= iniEigure 2' andv reference will; now be had to: this figure.

In this control.- system there is provided a. sump 1,0 to which the-fluidafrom' the driving motors-, etc.,.v is returned. From: this sump; fluid is drawnit-hrough the screen: 12 into-the pump unit 13,,as indicated. by the arrows, the pump unit, 1'31; being driven; fromthe motor by means otthez connection 14* in any conventional manner; The pump unit 13 is preferably; of the re.-

tary: abutment: type and has the three stages oi: pump pressure, ,thefirst stagedelivering fluid:

under: low -volume' but high pressure and pro.-

gressively increasingin volume and decreasing;-

in--,pressure through. the: other two' stages; these stages being-controlled by a suitablevalvemech anismwhiclrmay; be actuated through one'of the: control levers 13;

A, suitable: control: mechanism: is indicated: at

15,; whereby,- the fluid; under pressurefrom the pump 13 is valved for return when the vehicle isin neutral position back; to the sump 'l Utthrough the-line: lb, or forward into.- the clutch; throu h,

the line: Fl: The-clutch; indicated generally; at;

- lever 82, fluid may be transmitted through the line 83 and through the branch lines 84 to the fluid motors 85 corresponding to the fluid motors- 51 and 58 of Figure 3, whereby the fluid goes. through these-fluid motors, as indicated by the arrows, for imparting driving torque to the pinion shafts 59 and then returns to the sump through the" lines 86.

The, valve control. lever 82 when actuated in the opposite direction, causes the fluid in the control: member 8| to pass through line 81 and through branch lines 88 to the opposite connections: of. thefluid motors 85, thereby imparting; reverse torque tov the pinion shafts 59; In either event, the: discharge fluid from the wheel motors 85 passes through. the: lines- 85 andthrough suitable heat/ exchangers 89- bacls to: the sump, I0.

Interposed in the return lines 85. are suitable brake valves: 90-. controlled by footoperatedbra'kepedals 9i and- 92; Brake pedals- 91 and 92. are

i 50- arranged that they may be, used: selectivelyto' operatethe brake valves 9 0, throughitheishafts- 932 and 94-to brakeoneron the other-of the-wheat motors 85 by stopping, the discharge of fluid; therefrom; or" maybe jointly. operated when:- it

: is desired to impart braking.- effort to both-wheels.-

A; suitable handiservice brake 95- may also be provided for. parking purposes.

Mounted adjacent the wheeli meters 85 are reversing valve; mechanisms 96 which,.as.shown;

by thev dotted: linearrows, can. be used for reversing the directioni ofr'flow from: either the branch lilies-fli t 01*"8'8 to the wheel motors; The

H15 which is. pivotally mounted intermediateaoff its ends; at i061 The-link llli-has formedin its: one end a slot l9?! whichreceives-,apinrmember. Hlil'carrie'dby. the rocker arm 98-; The link. I05

has; iormedin' its other end a slot H19 in which? isreceived-ia pinmember llll secured to thedragi link. 3?. Itwilli benotedthat there, are: lost motion, cormectionsv i and. 1.07. inthe tiebar so.

that uponlmovement of the.rocker arm 99 to. the

left, for, example the. control lever 91 at the right will move through thespace, I02 and will" not be actuated; while the other control lever 9'! will immediately be actuated to provide for reversing actuationof" the valve mechanism 96.

thereby causing reverse torque to be applied to the associated pinion shaft 59 innormal operation with the vehicle y, proceeding forwardly and the steering wheel beingirotatediby the operator to make a left-hand turn,. the-control. bar 98 will actuate the revereing motor: 96 at the: left sidez of:lii'gurea4:;v

causing the reversal of the direction of;:fluid:flowto the: wheelmotor 85 associated? therewith, thereby-first slowingi'dow'n; rotation of; the? pinion shaft- 59: in i itsnormal direction, them stopping the; same: and: reversing: its: direction of rotation-- to Y produce? a= pivoting 1 movement: of the: truck:

a left turn direction,

The clutch 19 is used only as a means of interconnecting the fluid under pressure to the forward or reverse control valve 8| controlled by the lever 82. l'he amount of fluid under pressure which is admitted is controlled through the valve mechanism 15 associated with the fluid pump 73. Braking of the vehicle at any time may be effected through the brake pedals 9| and 92 which, as previously described, can be operated either independently or simultaneously.

It is therefore believed apparent that we have provided a novel type of industrial tractor which has a very short turning radius as well as considerably improved maneuverability in small areas, and in which the transmission of the motor power to the drive wheels of the vehicle is through suitable cushioning means, through the fluid connections which form a cushioned medium of transmitting the torque to the driving wheels, thereby not tnly increasing the initial draw bar pull of the tractor but, also, eliminating any shock loads being transmitted from the tractor to whatever vehicle or load the tractor is either towing or pushing.

Also, the present invention provides for greatly increased visibility by the driver over the forward end of the vehicle, as well a simplifying the operation of the vehicle from the standpoint of controlling the driving power during the turning of the vehicle.

We are aware that various changes may be made in certain details of the present invention and, therefore, do not intend to be limited except as defined by the scope and spirit of the appended claims.

We claim:

1. In an industrial tractor having a castermounted type rear steering wheel assembly, a front transverse axle assembly, drive wheels at the end thereof, an engine disposed rearwardly thereof, pump means driven by said engine for developing a variable fluid pressure, hydraulic drive motors for each of said wheels, control means for selectively varying the volume and pressure of said fluid, delivery means conducting said fluid from said control means to said motors, steering means for said rear steering wheel assembly, and separate control means actuated in response to movement of said steering means for independently reversing the direction of flow of said fluid through either of said motors to reverse the driving action of the associated drive wheel.

2. In an industrial tractor having a castermounted type rear steering wheel assembly, a front transverse axle assembly, drive wheels at the ends thereof, an engine disposed rearwardly thereof, pump means driven by said engine for developing a variable fluid pressure, hydraulic drive motors for each of said wheels, control means for selectively varying the volume and pressure of said fluid, delivery mean conducting said fluid from said control means to said motors, steering means for said rear steering wheel assembly, and separate control means actuated in response to movement of said steering mean for verse the driving action of the associated drive wheel, said separate control means providing for decreasing the flow of fluid to either motor prior to said reversing.

3. The tractor of claim 1 including selective means for braking said drive motor either selectively or conjointly by stopping the discharge of fluid therefrom.

4. The tractor of claim 1 including means interposed between said first-mentioned control means and said motors providing for forward or reverse drive of said motors independently of said steering means.

5. In an industrial tractor having a castermounted type rear steering wheel assembly, independent drive Wheels at each side of the forward end of said tractor, steering means for said rear steering wheel assembly including a vertically pivotally mounted hand steering wheel assembly, fluid pressure-developing means, fluid motors for each of said drive wheels actuated by fluid from said pressure-developing means and including control means providing for forward or reverse drive at varying speeds, and means associated with said steering means and independent of said control means for successively slowing down one driving motor and thence reversing its direction of drive as said steering means is progressively actuated in one turning direction.

6. The tractor of claim 5 including selectively controlled means for selectively or conjointly braking said driving motors by stopping the discharge of fluid therefrom.

7. The tractor of claim 5 including means interposed between said pressure-developing means and said control means for bypassing said control means to provide a neutral position for said tractor.

8. Drive means for an industrial tractor having a caster-mounted type rear steering wheel assembly and laterally spaced independent drive wheels at the forward end thereof, comprising a fluid pump driven from a power source, means associated with said pump for delivering fluid therefrom at a plurality of ranges of pressure and volume, fluid motors at each of said wheels, forward and reverse control means for said motors, means for either connecting said fluid delivery means to said control means or returning said fluid to said pump, steering means for said rear steering wheel assembly, and independent control means responsive to actuation of said steering means for selectively reversing said fluid motors independently of said forward and reverse control means.

ROBERT LAPSLEY. GEORGE L. TURNER. References Cited in the file of this patent UNITED STATES PATENTS Date 

